Patent EP 0 498 211 describes a stainless steel manifold which comprises a stainless steel body provided with an inlet conduit having a flow inlet for a fluid to treat, a filtrate outlet conduit having a filtrate flow outlet for a treated fluid termed filtrate, and a retentate outlet conduit having a retentate flow outlet for a treated fluid termed retentate.
This manifold has a bearing surface against which an end cassette of the cassette set comes to bear tightly. Through this bearing surface emerge cassette feed ports which moreover emerge into the inlet conduit, conveying cut-outs for the filtrate and cassette filtrate return ports which moreover emerge into the filtrate outlet conduit and cassette retentate return ports which moreover emerge into the retentate outlet conduit.
The cassette feed ports, the ends of the conveying cut-outs, the cassette filtrate return ports and the cassette retentate return ports are configured such that they communicate with conduits formed in the filter cassette in tightly bearing relationship against the bearing surface of the manifold.
When the filter cassette bears against the bearing surface of this manifold, the surface of this cassette on the same side as the manifold is in tightly bearing relationship against the conveying cut-outs. Great care must be taken to avoid the cut-outs damaging the surface of the cassette in tightly bearing relationship.